Asociologist plans to conduct a survey to estimate the percentage of adults who believe in astrology. how many people must be surveyed if we want a confidence level of 99% and a margin of error of four percentage points? a) if we assume nothing is known about the percentage to be estimated, we need to survey 1037 adults. b) if we use the information from a previous survey in which 26% of respondents said that they believed in astrology, then we would need to survey 1079 adults.